The Sum Of Two Numbers Is 21 And Their Difference Is 15
The problem given says that 2 unknown numbers are given, whose sum is equal to 21 and the difference is 15. Let's find the two numbers :When we add the two numbers :
X + Y = 21
The difference of two numbers :
X - Y = 15
Solution :
If we add the two equations eachother , then we can find the first number.
X + Y = 21 X - Y = 15 2X = 36 |
Let's divide 36 to 2 for the first number "X" .
X/2 = 18
First number is 18
X + Y = 21
So ;
18 + Y = 21
Y = 21 - 18
Y = 3
Second number is 3
Question & Answer
The Sum Of Two Numbers Is 21 And Their Difference Is 15 : 18 And 3